    Document EP-A-0 075 966 discloses an aileron system with ailerons each of which are slide mounted to a track member which is in turn pivotally mounted to a wing structure.    Documents GB-A-2 038 737 and WO 84/01343A show a high lift system with bearing devices for a flap which have a distance from each other along the flow direction.
High lift systems for aircraft comprise high lift flaps that are arranged on the main wing of the aircraft and can be adjusted between a retracted position, in which the flap continuously complements the wing profile in an essentially gapless fashion, and several extended positions, in which a gap of given width forms between the wing and the flap and the flap is adjusted to a predetermined angle relative to the wing profile. The extending of the flap is generally realized in the form of a motion that comprises a rearward displacement of the flap relative to the wing and therefore an extension of the effective wing profile on one hand and an increase of the angle of attack of the flap along with an increase of the profile camber and therefore an increase of the aerodynamic lift on the other hand. The air flowing with a high speed from the underside of the wing to the upper side of the flap through the gap forming between the flap and the wing during the extending motion additionally contributes to increasing the lift.
One noteworthy system among the nowadays most popular types of high lift systems is, in particular, the so-called Fowler flap. During the extension of this flap, it moves rearward and away from the wing such that the aforementioned gap between the wing and the flap is formed, wherein an increase of the angle of attack of the flap is superimposed on this motion, particularly in the advanced stages of the flap extension. This combined motion is also referred to as Fowler motion.
Another known arrangement is referred to as Dropped Hinge Kinematics or Hinged Flap Kinematics, wherein the high lift flap is supported on a flap lever such that it can be pivoted about a pivot point arranged underneath the wing. As the name implies, the flap moves about the pivot point situated underneath the wing during the extension, namely along a path that has the shape of a circular arc.
Both described connections between the flap and the main wing, as well as the described drive units, make it possible to displace the flap from a retracted state into several intermediate positions with medium displacement paths and angles of rotation, as well as into a completely extended state.
Different high lift systems are known from U.S. Pat. Nos. 4,725,026, 4,784,355 and 6,601,801.